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	It's hard for occasional GPIO code reader/writer to know if values 0/1 equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and GPIO_LINE_DIRECTION_OUT to help them out. NOTE - for gpio-amd-fch and gpio-bd9571mwv: This commit also changes the return value for direction get to equal 1 for direction INPUT. Prior this commit these drivers might have returned some other positive value but 1 for INPUT. Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com> Acked-by: Scott Branden <scott.branden@broadcom.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
		
			
				
	
	
		
			118 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			118 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0+
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/*
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 * Access to GPOs on TWL6040 chip
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 *
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 * Copyright (C) 2012 Texas Instruments, Inc.
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 *
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 * Authors:
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 *	Sergio Aguirre <saaguirre@ti.com>
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 *	Peter Ujfalusi <peter.ujfalusi@ti.com>
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 */
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/kthread.h>
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#include <linux/irq.h>
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#include <linux/gpio/driver.h>
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#include <linux/platform_device.h>
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#include <linux/bitops.h>
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#include <linux/of.h>
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#include <linux/mfd/twl6040.h>
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static int twl6040gpo_get(struct gpio_chip *chip, unsigned offset)
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{
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	struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
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	int ret = 0;
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	ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
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	if (ret < 0)
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		return ret;
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	return !!(ret & BIT(offset));
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}
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static int twl6040gpo_get_direction(struct gpio_chip *chip, unsigned offset)
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{
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	return GPIO_LINE_DIRECTION_OUT;
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}
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static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned offset,
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				    int value)
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{
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	/* This only drives GPOs, and can't change direction */
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	return 0;
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}
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static void twl6040gpo_set(struct gpio_chip *chip, unsigned offset, int value)
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{
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	struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
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	int ret;
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	u8 gpoctl;
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	ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
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	if (ret < 0)
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		return;
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	if (value)
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		gpoctl = ret | BIT(offset);
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	else
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		gpoctl = ret & ~BIT(offset);
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	twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl);
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}
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static struct gpio_chip twl6040gpo_chip = {
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	.label			= "twl6040",
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	.owner			= THIS_MODULE,
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	.get			= twl6040gpo_get,
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	.direction_output	= twl6040gpo_direction_out,
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	.get_direction		= twl6040gpo_get_direction,
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	.set			= twl6040gpo_set,
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	.can_sleep		= true,
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};
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/*----------------------------------------------------------------------*/
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static int gpo_twl6040_probe(struct platform_device *pdev)
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{
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	struct device *twl6040_core_dev = pdev->dev.parent;
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	struct twl6040 *twl6040 = dev_get_drvdata(twl6040_core_dev);
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	int ret;
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	twl6040gpo_chip.base = -1;
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	if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0)
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		twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */
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	else
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		twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */
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	twl6040gpo_chip.parent = &pdev->dev;
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#ifdef CONFIG_OF_GPIO
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	twl6040gpo_chip.of_node = twl6040_core_dev->of_node;
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#endif
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	ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, NULL);
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	if (ret < 0) {
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		dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
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		twl6040gpo_chip.ngpio = 0;
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	}
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	return ret;
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}
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/* Note:  this hardware lives inside an I2C-based multi-function device. */
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MODULE_ALIAS("platform:twl6040-gpo");
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static struct platform_driver gpo_twl6040_driver = {
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	.driver = {
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		.name	= "twl6040-gpo",
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	},
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	.probe		= gpo_twl6040_probe,
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};
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module_platform_driver(gpo_twl6040_driver);
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MODULE_AUTHOR("Texas Instruments, Inc.");
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MODULE_DESCRIPTION("GPO interface for TWL6040");
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MODULE_LICENSE("GPL");
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